Engine starter



V. BENDIX.

ENGINE STARTER.

APPLICATION FILED NOV. 1 1916.

1,404,971 10 Patented Jan.24,1922.

W1 TNESSES: Y 2* INVEIYTOR VINCENT BENDIX, 0F CHICAGO, ILLINOIS.

ENGINE STARTER.

Specification of Letters Patent.

Patented Jan. 241:, 1922.

Application filed November 17, 1916. Serial No. 131,957.

To all whom it may concern:

Be it known that I, VINCENT BENDIX, a citizen of the United States, residing at Chicago, Cook County, Illinois, have invented certain new and useful Improvements in Engine-Starters, of which the following is a specification.

My invention relates to astarter for an engines, such as a gas engine, and pertains to the transmission or drive interposed between the starting motor and the part of the engine to be started. This transmission is of that type exemplified in patents heretofore issued to me, more particularly No. 1,125,935, dated January 26,- 1915, which transmission is characterized by a driving member such as a rotatable screw shaft which is adapted to be driven through a yielding driving connection, such as a coiled spring, connected thereto and to an initial driving shaft, such as the extended armature shaft of an electric motor. This transmission is further characterized by a driving My present invention pertains to a new arrangement and cooperation'of the above mentioned parts. of the transmission characterized particularly by the location of the yielding driving connection in a position adjacent the starting motor and at the inner end of the screw shaft instead of the outer end, as shown in screw shaft is cap le of an'endwise or longitudinal movement and in the present instance the same is normally held inwardly in a direction towards the spring but is capable of a movement outwardl in a direction away from the spring w enever'the pinion teeth should abut end to end with the teeth of the fly-wheel, this endwise movement being against the tension of the spring which forms the yielding driving connection and acting to extend such spring. Under this construction and arrangement the clearance space which was provided in the device of my patent aforesaid adjacent the spring and outer end of the screw shaft is dispensed with and all danger of any spring coil dropping into any such space is avoided, and moreover by reason of the fact that the spring is extended instead of my patent aforesaid. The

compressed during the longitudinal movement of the screw shaft, the extent of such movement is increased.

In the drawing Fig. 1 is an elevation partly 1n section illustrating one embodiment of my invention and also illustrating a part of the starting motor and a part of a fly-wheelof the engine to be started; Fi 2 an elevation of the screw-shaft alone, and 1* 1g. 3 a detail View illustrating another way of securing one of the driving heads to the screw shaft. I

Referring to the embodiment of my invention as shown in the drawing, the motor, such as an electric motor, is indicated at A and the same is provided with a driving shaft 1 which may be either a separate shaft driven by the armature shaft or, as herein shown, the armature shaft extended. This shaft has its bearing at its outer end in the bushing 2 arranged in the bearing 3 at the outer endof a supporting bracket 4 which is here shown as secured to the casing of the motor. This shaft is mounted intermediate its length in a bearing 5 in one end of the motor casing.

The screw-shaft 6 is in the form of a sleeve mounted upon the driving shaft 1 w th its main screw threads intermediate its lengthand with other screw threads 6 at its inner end, the other or outer end of the screw shaft being provided with a collar 6", preferably integral therewith. Upon the screw threads 6 there screws the driving head 7 which also acts as the stop nut for the driving member or pinion hereinafter described. Tn. order to ecee'p the head 7 from unscrewing from the screw shaft a notch 6 is out into the end of the screw shaft and a portion of the adjacent metal of the head 7 is riveted into such notch."

The driving member is here shown as a pinion 8 which is screw threaded upon the main threads of the screw shaft and is adapted to mesh with the teeth 9 of the flywheel 9. i I

The resilient driving connection between the armature shaft and the screw shaft consists of a coiled spring '10 which is conected at its ends with said shafts respectively. In the present instance the connection is not direct but indirect through driving heads, to-wit, the driving head 7 already described and a second driving head 11, which is located adjacent the motor and in advance of the bearing 5. This head is secured to the "Add Mid

driving shaft 1 by means of a bolt or pin 12 and is provided with a cylindrical portion 11 which extends outwardly towards the inner end of the screw-shaft. T'he spring 10 is provided with eyes 10 and 10*, the former engaging the bolt 12 and the latter the stud or short bolt 13 which screws into the driving head 7.

he screw shaft is mounted both for retary movement and for endwise or longitudinal movement but it is kept in the normal position shown in F ig, 1 with a yielding pressure as by means of the spring 10 which holds the inner end of such screw shaft against the outer end of the cylindrical portion 11 of the driving head 11. However, the screw-shaft is capable of an endwise movement in a direction away from the spring, that is towards the right, there being clearance space provided at 14 between the collar 6 and the bushing 2 to permit of such endwise movement. This movement is against the tension of the spring 10 and acts to extend or draw out such spring. Conse}- quently in this construction and arrangement of parts there is no clearance space provided adjacent thespring as in the drive of my patent aforesaid and therefore no danger of any coil of the spring lodging or becoming wedged in any such space.

Describing the mode of operation and starting with the parts in their normal positionshown in Fig. 1, the starting of the electric motor causes a rotation of the shaft 1 and consequent rotation of the screw shaft through the resilient driving connection described. vThe pinion, 8 will thereupon be advanced longitudinally of the screw shaft inwardly towards the motor with the result that the same will mesh with the fly-wheel. When the inion has reached full mesh and its longitu inal movement has been stopped by the driving head or stop nut 7, it will rotate with the screw shaft and will consequently rotate the fly-wheel. When the engine has started on its own power the increased speed of rotation of" the fly-wheel will cause the automatic demeshing of the pinion, which will thereupon move back to the home position shown in Fig. 1, at which time it is resting against the collar 6.

If in the meshing operation the pinion teeth and fiy-wheel teeth should meet end to end the screw shaft will yield longitudinally, that isit would have an enforced movement toward the right against the tension of the spring 10, until the proper register of the teeth is obtained, whereupon the screw-shaft will move back to normal position shown and the meshing will continue until full meshing is secured.

In- Fig. 3 I have shown a modified form of construction of the driving head on the screw-shaft according to which such head 15 is secured to the screw-shaft by the key 16 supplemented by the employment of the stud 13 acting as a set screw by screwing inwardly through the wall of the head 15 and against the screw shaft.

I claim:

1. A starter for engines comprising a rodirection away from the spring, whereby the latter becomes extended.

2., A starter for engines comprising a ram tatable screw shaft having a yielding longitudinal movement, a pinion screwthreaded thereon for both longitudinal movement thereof and rotary movement therewith, and adapted to operatively 'engage a part of the engine to be started, and i a coiled spring connected at one end to the screw shaft and extensible to accommodate said longitudinal movement of the shaft due to improperengagement of the pinion with the engine part.

3. Astarter for engines comprising a rdtatable screw-shaft having a yielding longitudinal movement, a pinion screw-threaded thereon for both longitudinal movement thereof and rotary movement therewith, and adapted to operatively engage a part of the engine to be started, a driving shaft, and a driving connection between the latter shaft and screw-shaft including a coiled spring connected to said shafts, the screw-shaft being movable longitudinally in a direction away from the spring and against the tension thereof when the pinion is stopped in in its longitudinal movement by improper engagement with the engine part.

4. A starter for engines comprising a rotatable screw-shaft having a yielding longitudinal movement, a pinion screw-threaded thereon for 'both longitudinal movement thereof and rotary movement therewith, and adapted to operatively engage a art of the engine to be started, a driving s aft, and a driving connection between the two shafts, including a driving head secured to the driving shaft, anda spring connected with such head and the screw-shaft and normally holding the latter shaft towards the head with a yielding pressure but by its ex pansion permitting said longitudinal movementthereof when the pinion is stopped in its longitudinal movement by improper engagement with the engine part.

5. A starter for engines comprising a ro= tatable screw-shaft having a yieldin longitudinal movement, a pinlon screw-t readed thereon for both longitudinal movement pan'sio'n permitting said longitudinal movc-- ment thereof when the pinion is stopped in its longitudinal movement by improper engagementwith the engine part.

6. A starter for engines comprising a rotatable screw-shaft having a yielding longitudinal movement, a pinion screw-threaded thereon for both longitudinal movement thereof and rotary movement therewith, and adapted to operatively engage a part of the engine to be started, adriving shaft,,and a driving connection between the two shafts including a driving head secured to the driving shaft, a driving head secured to the inner end of the screw-shaft, and a coiledspring surrounding the first named head and se cured at its ends to the two heads respec tively, said spring normal-1y holding the screw-shaft against the first named driving head with a yielding pressure but by its expansion permitting said longitudinal movement thereof when thepinion is stopped in its longitudinal movement by improper en- 3 gagement with the engine part.

7. A starter for engines comprising arotatable screw-shaft having a yielding longitudinal movement, a pinion screw-threaded thereon for both longitudinal movement thereof and rotary movement therewith, and adapted to operatively engage a part of the engine to be started, a driving shaft, and a drlvin connection between the two shafts including a driving head secured to the drivin shaft, a driving head secured to the inner en of the screw-shaft, and a spring secured at its ends to the two heads respectively, said spring normall holding the screw-shaft towards the driving head of the driving shaft with a yielding pressure but by its expansion permiting said longitudinal movement sion permitting space between its outer end and said bearing v and having a longitudinal movement outwardly towards said bearing and through said space, a driving member mounted on the sleeve for both longitudinal movement thereof and rotary movement therewith, and a spring driving connection located adjacent the inner end of the driving shaft and connecting between it and the. inner end of the sleeve, such spring being arranged to resist said outward movement of the sleeve.

9. A starter for engines comprising a driva ing shaft, a bearing for the outer end thereof, a screw threaded sleeve mounted thereon with a clearance space between its outer end and said bearing, and having a longitudinal movement outwardly towards said bearing'and through said space, a pinion screw threaded on the sleeve for both longitudinal movement thereof and rotary movement therewith, and a coiled drive spring located 30 adjacent the inner end of the driving shaft and connecting between it and the inner end of the sleeve, such spring by its expansaid outward movement of the sleeve.

10. A starter for engines comprising a driving shaft, a screw-threaded sleeve mounted thereon, a pinion screw-threaded on such sleeve for both longitudinal movement thereof and rotary movement therewith,and a spring driving connectidnlocated adjacent the inner end of the drivin shaft and connecting therebetween and t e inner end of the sleeve, such connection includin acoiled spring surrounding the driving s aft and connected at its ends respectively'to, the

shaft and sleeve and such sleeve having enforced longitudinal movement in a direction away from the spring and against the tension thereof.

VINCENT .BENDIX. 

